In this experiment you will measure the muon lifetime. Muons have almost exactly the same properties as electrons except they are heavier. Muons can decay due to the mass difference between muons and electrons. Muons and electrons interact with matter only electromagnetically or by the weak nuclear force. Cosmic ray muons arise from the decay of pions which are produced by high energy collisions of incoming cosmic rays with nuclei in the atmosphere. This is the main experiment in which you will learn about particle detectors, phototubes, and fast logic electronics.

Glossary
COSMIC RAYS are a convenient and free source of energetic particles for high energy physics experiments. Cosmic ray muons will be used in an experiment to measure their decay.